Conditional knockout mice lacking K(ATP) channel subunits

描述（由申请人提供）：KATP通道是许多不同类型细胞和组织功能的组成部分。然而，尽管它们在近25年前首次被描述，但这些通道的生理和病理生理作用直到现在才在大多数组织中出现。电生理学和药理学方法已经允许很好地理解KATP通道的作用。KATP通道（Kir6.1, Kir6.2, SUR1， SUR2A和/或SUR2B亚基）的分子鉴定进一步提高了我们对这些通道分布和功能的认识。最重要的假设是，生理和病理生理事件受多种组织中存在的KATP通道活动的影响，不同组织类型中通道活动之间的同步相互作用决定了生理或病理生理结果的性质。传统的药理学方法不能在复杂的生物学环境中检验这一假设，因为这些化合物缺乏对不同组织类型中存在的不同类型的KATP通道所需的特异性。对于每个KATP通道亚基，传统的敲除小鼠模型已经开发出来，这些动物模型的可用性大大增加了我们对KATP通道在体内功能的了解。然而，由于该表达在所有体细胞中都被消除，因此在确定KATP通道亚基在复杂生物环境（如缺血/再灌注）中的作用时，使用这些动物提供了挑战。为了研究多种组织中存在的KATP通道的相互作用以及它们在不同组织类型中的同步相互作用，需要新的工具，其中仅在特定组织、细胞类型或亚细胞区室中消除KATP通道。因此，本提案的目的是生成四种条件敲除每个KATP通道亚基的小鼠模型。鉴于KATP通道的丰富多样性（无论是在其组织分布和分子组成方面），迫切需要产生缺乏每个KATP通道亚基的条件敲除小鼠。这些动物模型的发展不仅会对我们自己的研究产生广泛的影响，而且会对整个领域产生广泛的影响，因为作为这些研究的一部分产生的这些动物将使不同领域（心脏病学、内分泌学、神经学等）的研究人员能够解开KATP通道在健康和疾病中的组织特定功能。公共卫生相关性：atp敏感的K+通道是独特的，它们将细胞内能量代谢转化为细胞活性和兴奋性，它们在许多不同细胞类型的功能中起着非常重要的作用，它们有助于维持血糖水平，调节血流，参与神经递质的分泌和保护免受缺血性损伤。在生理和病理生理背景下，对KATP通道的研究出现了新的挑战，这些挑战无法用现有的工具（即使是可用的传统敲除小鼠）来解决，这就是我们提出产生新的转基因小鼠模型的理由，在这种模型中，KATP通道亚基可以在某些组织类型中特异性地删除。这些小鼠将与科学界广泛共享，无疑将在许多研究领域（除了我们自己的研究之外）导致对KATP通道研究的重大突破，这将对生物医学，行为和临床研究领域产生重大影响。

DESCRIPTION (provided by applicant): KATP channels are integral to the functions of many different types of cells and tissues. However, even though they were first described almost 25 years ago, the physiological and pathophysiological roles of these channels are only now emerging for most tissues. Electrophysiological and pharmacological methods have allowed for a good understanding of the roles of KATP channels. The molecular identification of KATP channels (Kir6.1, Kir6.2, SUR1, SUR2A and/or SUR2B subunits) has further advanced our knowledge regarding the distribution and function of these channels. The overriding hypothesis to be examined is that physiological and pathophysiological events are subject to the activity of KATP channels that are present in multiple tissues and that synchronous interaction between channel activities in diverse tissue types determines the nature of the physiological or pathophysiological outcome. Conventional pharmacological methods cannot be used to examine this hypothesis in a complex biological setting since these compounds lack required specificity for different classes of KATP channels present in diverse tissue types. Conventional knockout mouse models have been developed for each of the KATP channel subunits and the availability of these animal models has added significantly to our knowledge of the functions of KATP channels in the in-vivo setting. However, since the expression is eliminated in all somatic cells the use of these animals provides challenges when defining the roles of KATP channel subunits in complex biological settings (such as ischemia/reperfusion). To examine the interplay of KATP channels present in multiple tissues and their synchronous interaction in diverse tissue types, new tools are needed in which KATP channels are eliminated only in specific tissues, cell types or subcellular compartments. The purpose of this proposal is therefore to generate four mouse models of conditional knockouts of each of the KATP channel subunits. Given the rich diversity of KATP channels (both in terms to their tissue distribution and molecular composition), a dire need exists to generate conditional knockout mice devoid of each of the KATP channel subunits. The development of these animal models will have a wide ranging impact, not only on our own research, but also on the field in general since these animals generated as part of these studies will allow investigators working in diverse areas (cardiology, endocrinology, neurology, etc) to unravel the tissue specific functions of KATP channel in health and disease. PUBLIC HEALTH RELEVANCE: ATP-sensitive K+ channels are unique in that they transduce intracellular energy metabolism to cellular activity and excitability and they have very important roles on the functions of many different cell types and they help to maintain blood glucose levels, regulate blood flow, participate in the secretion of neurotransmitters and protect against ischemic insults. New challenges have arisen in the study of KATP channel in physiological and pathophysiological context that cannot be addressed using existing tools (even with the available conventional knockout mice), which is the rationale for our proposal to generate new genetically altered mouse models in which KATP channel subunits can be deleted specifically in certain tissue types. These mice, which will be widely shared with the scientific community, will undoubtedly lead to significant breakthroughs in the study of KATP channels in many study areas (in addition to our own research) and this will have a major impact on the fields of biomedical, behavioral and clinical research.